An exchange fund is a limited partnership in which all partners share the problem of having a concentrated position in a highly appreciated stock- by contributing shares of their securities in exchange for interests in a partnership comprised of investors in similar situations (other unicorn-like companies ex. Airbnb), they can diversify their holdings without incurring immediate capital gains tax. Would employees and management teams at pre-IPO companies be open to such an idea? Would they be okay with a 3 year lock up?